尼羅草最上葉領高度與產量及品質的關係

Relationships between Toppest Leaf Collar Height and Forage Yield or Quality of Nilegrass

蕭素碧(Sue-Pea Shaug) ； 許進德(Chin-Te Hsu)

《中華農學會報》 8卷3期 (2007/06) Pp. 210-224

https://doi.org/10.6730/JAAC.200706_8(3).0003

摘要

以尼羅草(Acroceras macrum) AC14、NLT1（尼羅草台畜草一號）、AC26及AC30等四個不同基因質的品系為材料，於2002年之春、夏及秋等三季，每季從生長14天至91天每週調查農藝性狀包括最上葉領高度(TLCD)、株高(PH)、乾物率、葉／莖比(L/S)及乾物產量(DMW)等，並分析粗生白質(CP)、酸洗(ADF)及中洗(NDF)纖維及相對飼養值(RFV)等牧草品質，結果TLCH、PH、L/S、DMW、CP、ADF、NDF及RFV等於不同季節、割期及品系間皆表現極顯著的差異，且受季節、割期及品系間交感的影響。DMW於品系間以AC30之6.0公噸／公頃／次最高，其次為NLT1之5.6公噸／公頃／次，CP以AC26及AC30最高，分別認12.1及11.5%，彼此間差異不顯著，ADF及NDF以NLT1最高，AC30皆居中，RFV以AC14之128最高，AC30之121居中，由上知AC30具高的DMW及CP，中等量的ADF、NDF及RFV，此結果顯示牧草選育可同時選到高產及高品質的品系。而DMW平均以夏季最高，CP及RFV以春季最高，ADF及NDF以春季最低，顯示春季乾草具較佳的品質。四個品系於三個季節將TLCH與產量或品質進行相關分析，結果除秋季AC14品系之TLCH與ADF、NDF及RFV與等相關不顯著外，其餘TLCH皆與DMW、CP、ADF、NDF及RFV等呈極顯著相關。進一步以TLCH為自變數進行直線廻歸分析，亦除秋季AC14之ADF、NDF及RFV等之廻歸係數不顯著外，其餘皆達極顯著水準，於春季TLCH對OMW、CP、ADF、NDF及RFV等之廻歸決定係數(R^2)平均達0.77，剩餘機差(RMSE)為3.35，於夏季R^2平均達0.76，RMSE為2.94，而於秋季R^2為0.46，RMSE為3.47，顯然於秋季除TLCH外尚存有其他不明因素影響著產量及品質，由上可知於三個季節種植不同品系的尼羅草，可於田間直接測量TLCH，之後代人直線廻歸程式，可以簡單有效地預估DMW、CP、ADF、NDF及RFV等供收穫管理的參考。

關鍵字

尼羅草 ； 最上葉領高度 ； 牧草產量 ； 牧草品質

並列摘要

The plants of four nilegrass (Acroceras macrum) germplasms, i. e., AC14, NLT1 (CV. Nilegrass Taishi No. 1), AC26 and AC30 were tested weekly to determine the relationships between toppest leaf collar height (TLCH) and forage yield and quality from the 14(superscript th) day after cutting (DAC) to the 91(superscript th) DAC in spring, summer and fall of 2002, respectively, The results showed that TLCH, plant height (PH), leaf/stem (LSR), dry matter weight (DMW), crude protein (CP) acid (ADF) and neutral (NDF) detergent fibers and the relative feeding value (RFV) were significantly different among the three growth seasons, cutting stages and hoes, Line AC30 had the highest DMW with 6.0 mt/ha/cut, followed by NLT1 with 5.6 mt/ha/cut. AC30 had higher CP 11.5%, moderate ADF, NDF and RFV. It indicated that AC30 might produce higher Image yield wit better quality. DMW was the highest in summer, yet the highest CP and RFV and the lowest ADE and NDF were shown in spring. Our study showed that nilegrass could produce forage with better quality in spring. The correlation coefficients between TLCH and DMW, CP, ADF, NDF or RFV and the regression coefficients by TLCH as an independent variable, with DMW, CP, NDF, NDF and RFV as dependent variables o four lines in three seasons were highly significant, respectively, except ADF NDF and RFV of AC14 in fail. The averages of regression determination coefficients (R^2) of DMW, CP, ADF, NDF and RFV of four lines sere 0.77, 0.76 an 0.46 and the root mean square errors (RMSE) of those were 3.35, 2.94 and 3.47 in three seasons, respectively. Obviously other factors also affected the forage yield and quality in fall. From above-motioned results, TLCH could provide useful information for harvest management of nilegrass by using linear regressions to predict DMW, CP, ADF, NDF and RFV in the held directly.

並列關鍵字

Nilegrass Acroceras Macrum ； Toppest Leaf Collar Height ； Forage Yield ； Forage Quality